Soybean dehuller

ABSTRACT

The hulls of soybeans are separated from the cotyledons by thrusting the soybeans into a perforated plate which serves to rupture the hulls and permit the separation of the cotyledons therefrom. This thrusting action is imparted to the soybeans by means of compressed-air flow through a nozzle to create a partial vacuum carrying the soybeans to the orifice of the nozzle and thereafter the compressed-air flow serves to expel the soybeans into a perforated plate rupturing the soybean hull and permitting the cotyledons to be separated from the hulls. The apparatus which may be used in carrying out this method of dehulling soybeans consists of a chamber having a restricted orifice through which compressed air is permitted to flow thereby creating a partial vacuum in the chamber which is effective to permit soybeans introduced thereto to be expelled through the restricted orifice and into a perforated plate for the subsequent separation of the hulls from the cotyledons.

United States Patent Lee J. Nahm, Jr. St. Louis, Mo. [21] Appl. No. 775,275

[22] Filed Nov. 13, 1968 [72] Inventor [45] Patented Feb. 9, 1971 [73] Assignee The Ralston Purina Company St. Louis, Mo. a corporation of Missouri [54] SOYBEAN DEHULLER 1 Claim, 1 Drawing Fig.

'[52] U.S.Cl 146/253,

Primary Eiqminer-Willie G. Abercrombie Attorneys-R. W. Brukardt and L. .1 Hurst ABSTRACT: The hulls of soybeans are separated from the cotyledons by thrusting the soybeans into a perforated plate which serves to rupture the hulls and permit the separation of the cotyledons therefrom. This thrusting action is imparted to the soybeans by means of compressed-air flow through a nozzle to create a partial vacuum carrying the soybeans to the orifree of the nozzle and thereafter the compressed-air flow serves to expel the soybeans into a perforated plate rupturing the soybean hull and permitting the cotyledons to be separated from the hulls. The apparatus which may be used in carrying out this method of dehulling soybeans consists of a chamber having a restricted orifice through which compressed air is permitted to flow thereby creating a partial vacuum in the chamber which is effective to permit soybeans introduced thereto to be expelled through the restricted orifice and into a perforated plate for the subsequent separation of the hulls from the cotyledons.

PATENTEU FEB 9197:

INVENTOR LEE J. NAHM, JR. av

SOY BEAN DEHULLER BACKGROUND OF THE INVENTION In the past the hulls of soybeans have been separated from the cotyledons by initially subjecting the soybeans to a mechanically rotated blade arrangement such that centrifugal force was effective to propel the soybeans into a plate which ruptured the hulls and permitted the separation of the hulls from the cotyledons. Thereafter the separated particles were subjected to air currents or to a mechanical separator which was effective in separating the hulls from the cotyledons due to the relative weights of the particles.

It is the object of the present invention to provide a means for separating the hulls from the cotyledons of soybeans which utilizes only air currents to effect the rupturing and separation of the hulls from the cotyledon portion. Accordingly, this is accomplished by providing a tubelike chamber having an inlet and a restricted outlet orifice and providing a compressed-air nozzle in substantial alignment with the restricted orifice such that as compressed air is forced from the nozzle through the restricted orifice a vacuum is created in the tubular chamber which permits soybeans introduced into the inlet of the chamber to be expelled through the restricted orifice with such a velocity that when they strike a perforated plate in alignment with such orifice the hulls are ruptured and the cotyledons may be separated therefrom.

SUMMARY OF THE INVENTION A general object of the present invention is to provide a simplified method of effecting the separation of hulls from the cotyledons of soybeans.

Another object of the present invention is to provide an apparatus which utilizes solely compressed air to expel soybeans therefrom into means for effecting the rupturing and separation of the hulls from the cotyledons of soybeans.

Briefly, the present invention comprises a method of separating the hulls from the cotyledon portion of soybeans by utilizing compressed air to propel soybeans into a perforated plate. Another aspect of the present invention is to provide an apparatus having a tubelike chamber with an inlet and a restricted orifice and having compressed-air flow in registry with the restricted orifice whereby soybeans introduced to the inlet of said chamber are expelled I therefrom by the compressed air into a plate member for effecting the separation of the hulls and cotyledon portions of soybeans.

BRIEF DESCRIPTION OF THE DRAWING The drawing is a cross-sectional view of the dehuller apparatus embodying the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing, the bean dehuller 1 is provided with a cylindrical housing 2 having a restricted orifice or nozzle opening 3 at the leftward end thereof and being closed by a wall portion 4 at the rightward end thereof. An inlet 5 is provided in the housing 2 adjacent to the rightward end wall 4 and is connected to a source of soybeans having the hulls thereon for subsequent removal. An aperture 6 is provided in the end wall 4 and has inserted therethrough an axially extending supply pipe 7. The rightward end of the pipe 7 is connected to a suitable source of compressed air (not shown) and the leftward end thereof is provided with a restricted outlet or orifice 8. It should be noted that the restricted orifice 8 of the supply pipe 7 is in registry with the orifice 3 of the chamber 2 such that compressed air flowing through the pipe 7 may be emitted in a straight line through the orifice 3. As is obvious, by properly positioning the orifice 8 with respect to the orifice 3, compressed air forced from the orifice 8 through the orifice 3 will be effective to create a partial vacuum in the chamber 2 which will serve to pull air and particles contained therein through the inlet 5 and the chamber 2 to be emitted from the orifice 3. A perforated plate 9, provided with suitable mounting means. is positioned at an acute angle to the orifice 3 and is spaced a predetermined distance therefrom such that as soybeans are ejected from the chamber 2, they will strike the plate 9 with the impact serving to separate the parts of the beans. Any suitable means, such as air currents, vibrators, etc. which are well known in the art may be utilized for dividing the separated hulls from the cotyledons.

In the :operation of the bean dehuller l, compressed air is forced through the supply pipe 7 and nozzle 8 and through the orifice 3 whereby a partial vacuum in chamber 2 is established, as previously described. Soybeans are then supplied to the inlet 5 with the vacuum in the chamber 2 being effective to carry the soybeans to the nozzle area 3 and thereafter the compressed air is effective to propel the soybeans from the nozzle area 3 to impact the plate 9. The beans are impinged against or strike the plate 9 with a high velocity and force and since the plate 9 is perforated, the air does not serve as a cushion for the beans, thereby permitting the collision of the bean with the perforated plate to rupture the soybean hull and permit the separation of the cotyledon portion of the soybean from the hulls. The hulls and cotyledons are then collected in the bin 10 and are thereafter removed for subsequent separation and processing.

It should be understood that the velocity with which the soybeans strike the perforated plate 9 should be adjusted so that when the beans strike this plate, a rupturing of the hulls will occur permitting the subsequent separation of the cotyledon portion therefrom. This may be accomplished either by controlling the pressure of the compressed air supplied to the pipe 7 or by adjusting the distance between the nozzle 3 and the perforated plate 9. It has not been established exactly what force is necessary for the hulls to be separated from the cotyledon portion of the beans; however, this can be readily determined by making the aforementioned adjustments as too little force will not separate the bean components, while too much force will result in the destruction of.

the components. The operator, by making a few minor adjustments, can control the proper velocity with which the beans strike the perforated plate 9.

It has been found that by giving the soybeans a heat treatment prior to their' introduction into the dehulling apparatus 1, the hulls of the soybeans break apart more readily and improved dehulling characteristics are obtained. The heat treat ment should be carried out in a dry heat such as heated air or combustion gases. The hot air or combustion gas atmosphere into which the soybeans should be introduced may vary from 175 F. to about 500 F. for about 60 minutes to about 10 seconds, respectively. Preferably, the temperature range will be between 250 F. 450 F., with the time range being between 10 minutes -25 seconds, respectively. This use of the controlled dry heating of the soybean is effective to cause the hull of the soybean to split, resulting in better dehulling characteristics when the soybeans strike the perforated plate 9.

From the foregoing, it is now apparent that a novel apparatus and method for dehulling soybeans meeting the objects and advantages set out hereinbefore, as well as other objects and advantages apparent in the disclosure, are provided and that changes or modifications as to precise configurations, shapes and details as set forth in the disclosure by way of illustration may be made by those skilled in the art without departing from the spirit of the invention, as defined by the claims which follow.

lclaim:

1. Apparatus for separating the cotyledons from the hulls of soybeans comprising a housing having an inlet, a tapered restricted outlet orifice in said housing, supply means in said housing extending coaxially into said housing and including other restricted orifice means in registry with and closely associated to said first-named orifice means, said supply means being connected to a compressed-air source whereby compressed air supplied thereto and expelled through said other and' first-named orifice means is effective to create a partial vacuum in said housing permitting soybeansintroduced into 'said inlet to be carried by the partial vacuum to said first named orifice and thereafter the compressed air being effective to propel the soybeans from said housing, the close association of said first named and other orifice means being sufficient to permit the" soybeans to beexhausted from said housing without substantially contacting said housing between said 

